Several museum information processing systems are discussed in relation to their underlying assumptions regarding museum information and networking needs that have resulted in inadequate service to some kinds of museums, particularly historical museums. Rather than any of these systems, a modular approach is proposed that would allow each museum to fulfill its own self-determined information needs in the most flexible and least expensive manner possible. Information processing systems discussed include GRIPHOS (General Retrieval and Information Processor for Humanities-Oriented Studies) and the constraints placed on it by the MCN (Museum Computer Network); SELGEM (Self-Generating Master)--a package of generalized computer programs developed by the Information Systems Division of the Smithsonian Institution primarily for use by museums for general information processing, collection documentation, and for related research-oriented projects; MIRS (Meta Information Retrieval System) and the W.H. Over Museum System--each based upon the same assumption that museum information needs will be served if they have an adequate index to their collections; and GIPSY (Generalized Information Processing System) which assumes that rapid retrieval and display of specific records is the most important need to be satisfied. (Author/MBR)